In a conventional display apparatus including two independent visual indicators, each indicator is independently driven using separate integrated circuit pins and separate current limiting resistors. This type of conventional display apparatus is problematic in that it is "pin constrained". In other words, an excessively large number of integrated circuit pins are required to drive a large scale display apparatus. Notably each additional pin in an application specific integrated circuit has a tangible cost associated with it. In other words, each additional pin required to drive the visual indicators eliminates other possible functions or forces the use of a larger and more expensive integrated circuit package.
Moreover, conventional display apparatus require that a separate current limiting resistor be provided for each independently driven visual indicator. This is problematic in that it increases the scale of the display apparatus.
Accordingly, a primary object of the present invention is to provide an improved display apparatus in which a only single integrated circuit output pin is needed to selectively drive two dependent visual indicators.
Another object of the present invention is to provide such an improved display apparatus in which a single current limiting resistor is used to drive two independent visual indicators, thereby reducing the size of the display apparatus relative to many conventional display apparatus.